Evaluation of Angiogenic Factor Release From Thermosensitive Poly(N-Vinylcaprolactam)-g-Collagen: In Vitro and In Vivo Studies

  • Serap Durkut Ankara University, Tissue Engineering, Biomaterials and Nanobiotechnology Laboratory, Ankara, Turkey



In this study, a thermosensitive poly(N-vinylcaprolactam)-g-collagen (PNVCL-g-Col) hybrid hydrogel was synthesized by conjugation using the NHS/EDC cross-linking sys-tem, and characterized. At first, the efficiency of in vitro sustained delivery of human vas-cular endothelial growth factor (VEGF) from the thermosensitive PNVCL-g-Col hydrogel modified with heparin, was evaluated for duration of ten days under in vitro physiological conditions (37oC, pH 7.4). The results indicated that PNVCL-g-Col hydrogel preserved its stability and released ~90% of the loaded VEGF within this time period. In vitro study showed that PNVCL-g-Col was basically histocompatible. Then, the in vivo angiogenic activity of the VEGF-releasing PNVCL-g-Col was investigated using a subcutaneous rat model. In vivo study confirmed that angiogenic-factor-loaded PNVCL-g-Col had the ca-pacity to induce neovascularization indicating that the in vivo bioactivity of the VEGF was preserved in the thermosensitive PNVCL-g-Col.


Waste tire; Thermosensitive polymer; Sustained release; Conjugation; Angiogenesis; Hybrid hydrogel; VEGF.

DOI: 10.17350/HJSE19030000121

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How to Cite
Durkut, S. (2019). Evaluation of Angiogenic Factor Release From Thermosensitive Poly(N-Vinylcaprolactam)-g-Collagen: In Vitro and In Vivo Studies. Hittite Journal of Science & Engineering, 6(1), 57-61. Retrieved from https://www.hjse.hitit.edu.tr/hjse/index.php/HJSE/article/view/HJSE19030000121